All posts by Gunther Arnold

POWER PLANT: Two Rolls-Royce Merlin 76/77 liquid-cooled engines, rated at 1,250 hp each

PERFORMANCE: 387 mph at 26,000 ft

COMMENT: The Westland Welkin was a British twin-engine heavy fighter from the Westland Aircraft Company, designed in 1940 to fight at extremely high altitudes, in the stratosphere. Westland had some expertise in twin-engine aircraft; its Whirlwind Mk.I escort fighter was in full production. The word Welkin means “the vault of heaven” or the upper atmosphere. As mentioned, first conceived in 1940, it was built from 1942–43 in response to the arrival of modified Junkers Ju 86P bombers flying reconnaissance missions that suggested the German Luftwaffe might attempt to re-open the bombing of England from high altitude. But the threat was never materialized. Consequently, Westland produced only a small number of Welkins. In total 77 aircraft were built but only few of these flew. Most of the aircraft were produced without engines. One sole aircraft was modified as Welkin II which had a lengthened nose to accommodate A.I. radar (Ref.: 23).

COMMENT: The Heinkel He 114 was a sesquiwing reconnaissance seaplane produced for the German Kriegsmarine (German Navy) in the 1930s for use from warships. It replaced the company’s Heinkel He 60, but did not remain in service long before being replaced in turn by the Arado Ar 196 as standard spotter aircraft.
While the fuselage and flotation gear of the He 114 were completely conventional, its wing arrangement was highly unusual. The upper set of wings was attached to the fuselage with a set of cabane struts, as in a parasol wing monoplane, whereas the lower set was of much lesser span while having approximately the same chord. This general layout is not especially unusual, and is known as a “Sesquiplane”, or a biplane which has a smaller lower wing. Typically, the lower wing is about 3/4 of the span of the upper wing, and has a smaller chord as well. The He 114 has a much shorter lower wing than usual, but has the same chord as the upper wing, which keeps the wing area ratio similar.
The He 114 was never a great success, was not built in large numbers, and served with the Luftwaffe for only a short time. While the Heinkel He 60 had handled very well on the water but been sluggish in the air, the He 114’s handling while afloat was poor and its performance in the air scarcely better than the aircraft it replaced (Ref.: 24).

POWER PLANT: Two BMW VI 6.0 liquid-cooled engines, rated at 660 hp each

PERFORMANCE: 137 mph at sea level

COMMENT: The Heinkel He 59 was a German biplane designed in 1930 resulting from a requirement for a torpedo bomber and reconnaissance aircraft able to operate with equal facility on wheeled landing gear or twin-floats.
In 1930, the Heinkel Aircraft Company began developing an aircraft for the Reichs­marine, precursor of the Kriegsmarine. To conceal the true military intentions, the aircraft was officially a civil aircraft. The Heinkel He 59B landplane prototype was the first to fly, an event that took place in September 1931, but it was the He 59A floatplane prototype that paved the way for the He 59B initial production model, of which 142 were delivered in three variants. The Heinkel He 59 was a pleasant aircraft to fly; deficiencies noted were the weak engine, the limited range, the small load capability and insufficient armament.
The keels of the floats were used as fuel tanks – each one holding 900 l of fuel. Together with the internal fuel tank, the aircraft could hold a total of 2,700 l of fuel. Two fuel tanks could also be placed in the bomb bay, bringing the total fuel capacity up to 3,200 l. The propeller was fixed-pitch with four blades.
During the first months of WW II, the He 59 was used as a torpedo- and minelaying aircraft. Between 1940 and 1941 the aircraft was used as a reconnaissance aircraft and in 1941-42 as a transport, air-sea rescue, and training aircraft. In total 142 aircraft were built in various subtypes. The trainer and air-sea rescue version was designated Heinkel He 59D-1. The trainer models survived slightly longer in service than operational models, but all had been retired or destroyed by 1944 (Ref.: 24).

COMMENT: Appearing too late to serve in its intended role, the Kawanishi N1K1 “Kyofu (“Mighty Wind”) floatplane fighter participated only briefly in combat operations but it sound design led to its adaptation into one of the most successful land-based fighter aircraft of WW II, the Kawanishi N1K1-J “Shiden”.
Development of a series of floatplane fighters intended to provide air support to Japanese amphibious landing forces in areas where no airfield existed was initiated in 1940, while Nakajima Hikoki K.K. undertook the development of an interim aircraft – the A6M2-N – Kawanishi Kokuki K.K were instructed to initiate the design of an aircraft specially conceived for that purpose. Issued by the Japanese Navy in September 1940 planning began immediately in the Kawanishi engineering office. Basing their efforts on the advanced technology developed for the Kawasnishi E15K1 “Shiun”, a team of engineers designed a compact floatplane with mid-mounted wings of laminar-flow section. Like the “Shiun”, the projected floatplane fighter, then known by the designation of K-20, was to be powered by a 1,460 hp Mitsubishi MK4D “Kasei 14” driving two contra-rotating two-blade propellers to offset the anticipated propeller torque on take-off. The central float was to be attached to the fuselage by a V-strut forward and an I-strut at the rear, but the proposed use of retractable stabilizing floats with metal planning bottom and inflatable rubberized-fabric tops could be traced to the “Shiun’s” design philosophy. Difficulties encountered with this type of float during the early part of E15K1 flight trial programme led to their replacement by fixed cantilever floats prior to the aircraft’s first flight.
Following the completion the first N1K1 made its successful maiden flight on 6 May, 1942. However, teething troubles with the contra-rotating propeller gear box – similar to those experienced in the E15K1 programme – led to the decision to replace the “Kasei 14” engine by a MK4C “Kasei 13” driving conventional three-blade propeller via an extension shaft. Once in the air the N1K1 was an extremely pleasant aircrafts to handle and the use of combat flaps gave it remarkable maneuverability. Finally, based on these good results the Japanese Navy ordered the aircraft into quantity production as the Navy Fighter Seaplane “Kyofu Model 11”, (Kawanishi N1K1 “Kyofu”) and deliveries of production aircraft began in spring 1943 (Ref.: 1).

COMMENT: Satisfied with the results of the flight trial progamme of the prototypes of the Kawanashi N1K1 the Imperial Japanese Navy ordered the aircraft into quantity production as the Navy Fighter Seaplane “Kyofu Model 11”, and deliveries of production aircraft began in spring of 1943 following the completion of eight prototypes and Service trials aircraft. But production was slow in gaining tempo and by December 1943, when the delivery rate had reached fifteen aircraft per month, the decision was taken to cease manufacture of the “Kyofu” and the last N1K1 was delivered in March 1944. This decision did not indicate any misgiving on the aircraft’s capability but merely reflected the fact that the war had taken an unfavourable turn for Japan which no longer needed a fighter to support offensive operations.
The war situation was also reflected in the operational use of the aircraft in a defensive role and N1K1s (Allied code name “Rex”) were assigned as interceptors in the Borneo Area of Action. Late in the war the “Kyofu” was assigned to similar duties with the Otsu Kokutai operating from Lake Biwa as an air defence unit (Ref.: 1).

POWER PLANT: Two BMW 801G-2 air-cooled radial engines, rated at 1,700 hp each

PERFORMANCE: 310 mph

COMMENT: The Junkers Ju 188 was a German Luftwaffe high-performance medium bomber built during WW II, the planned follow-up to the famous Junkers Ju 88 with better performance and payload. It was produced only in limited numbers, due both to the presence of improved versions of the Ju 88, as well as the increasingly effective Allied strategic bombing campaign against German industry and the resulting focus on fighter production.
In grand total 1,234 aircraft were delivered until the end of the war in several subtypes Junkers Ju 188A & E, C, D & F, G & H, and R. The Ju 188 was designed to be fitted with either the 1,730 hp Jumo 213A or 1,680 hp BMW 801 G-2 engines without any changes to the airframe, with the exclusion of the re-design for Jumo-powered examples, of the annular radiators from their Jumo 211 layout for the A-series to better match the more powerful 213’s cooling needs, while still using essentially the same broad-chord three-blade propellers as the A-series did. It was originally intended that both would be known as A models, but the naming was later changed: the Ju 188A model powered by the Jumo 213, and the Ju 188E by the BMW 801.
The first three production Ju 188 E-1 machines were delivered with the BMW engines in February 1943, another seven in March, and eight in April. A special unit for conversion testing was formed up in May 1943, after testing the aircraft were attached to an operational unit, with the first mission taking place on 18 August 1943. By the end of the year, 283 Ju 188s had been delivered (including Ju 188Fs), and two new factories were added to the production effort. Most operational machines differed from the prototypes only in having a 20 mm MG 151/20 cannon in the nose and dorsal turrets in place of the 13 mm MG 131. The MG 131 I was intended to be used in the Ju 188 E-1 or the G-2. But the heavy armament in the A and E series was the MG 151/20. The Junkers Ju 188 E-2 was built as a torpedo bomber, but was identical to the Junkers Ju 188 A-3 (Ref.: 24).

POWER PLANT: Two BMW 801G-2 air-cooled radial engines, rated at 1,700 hp each

PERFORMANCE: 310 mph

COMMENT: A modified torpedo bomber version of the German Luftwaffe high-performance medium bomber Junkers Ju 188 was the Junkers Ju 188E-2. These aircraft differed from the Junkers Ju 188E-1 by mounting a small, low-UHF-band FuG 200 “Hohentwiel” sea-search radar set under the nose (not shown on these pictures) and shackles for a torpedo for naval strike missions. The aircraft were delivered as the Ju 188 E-2 with BMW 801 air-cooled radial engines, and with the Jumo as the Ju 188 A-3. The only other difference was the removal of the outer pair of wing bomb shackles (Ref.: 24).

POWER PLANT: Two Wright GR-2600 radial engines, rated at 1,700 hp each

PERFORMANCE: 305 mph at 11,600 ft

COMMENT: Derived from the Martin A-22 “Maryland” the “Baltimore” had a deeper fuselage and more powerful engines. It met the needs for a light to medium bomber, originally ordered by the Anglo-French Purchasing Commission as a joint project in May 1940. The French Air Force sought to replace the earlier “Maryland”; 400 aircraft being ordered. With the fall of France, the Royal Air Force (RAF) took over the order and gave it the service name “Baltimore” To enable the aircraft to be supplied to the British under the Lend-and-Lease Act the U. S. Army Air Forces designation A-30 was allocated. In total 1.175 aircraft provided to the RAF.
The first British aircraft were delivered in late 1941 to equip Operational Training Units. Later, the RAF only used the “Baltimore” operationally in the Mediterranean theater and North Africa.
Many users were impressed by the step up that the “Baltimore” represented from older aircraft like the Bristol “Blenheim”. The users of the “Baltimore” praised the aircraft for its heavy armament, structural strength, maneuverability, bombing accuracy, and relatively high performance, but crews complained of cramped conditions similar to those in the earlier “Maryland” bomber. Due to the narrow fuselage it was nearly impossible for crew members to change positions during flight if wounded – the structure of the interior meant that the pilot and observer were separated from the wireless operator and rear gunner. This was common for most light bombers of the era like the Handley Page “Hampden”, Douglas “Boston” and Bristol “Blenheim”. Pilots also complained about the difficulties in handling the aircraft on the ground. On take-off, the pilot had to co-ordinate the throttles perfectly to avoid a nose-over, or worse. Thrown into action to stop Rommel’s advance, the “Baltimore” suffered massive losses when it was utilized as a low-level attack aircraft, especially in the chaos of the desert war where most missions went unescorted. However, operating at medium altitude with fighter escorts, the “Baltimore” had a very low loss rate, with the majority of losses coming from operational accidents.
Undertaking a variety of missions in the Middle East, Mediterranean and European theaters, the “Baltimore’s” roles included reconnaissance, target-towing, maritime patrol, night intruder and even served as highly uncomfortable fast transport. The “Baltimore” saw limited Royal Navy Fleet Air Arm service with aircraft transferred from the RAF in the Mediterranean to equip a squadron in 1944. More than 1.500 aircraft with a variety of subtypes rolled out of the Martin Company. The “Baltimore” Mk.III depicted here was supplied under Lend-and-Lease Act to the RAF, two 0.50 in machine guns in a Martin-built electrically powered dorsal turret (Ref.: 24).

COMMENT: The Blohm & Voss Ha 139 was an all-metal inverted gull wing floatplane. With its four engines it was at the time one of the largest float-equipped seaplanes that had been built. The inboard engines were mounted at the joint between the inboard anhedral and outboard dihedral wing sections, above the pylon-mounted floats.
The aircraft were flown by Deutsche Luft Hansa (DHL) on transatlantic routes between 1937 and 1939. Catapult-launched from an aircraft tender they were able to transport 500 kg of mail over a distance of up to 5,000 km.
On the outbreak of WW II, the planes were transferred to the Luftwaffe and used for transport, reconnaissance and minesweeping work over the Baltic Sea. They were not particularly suited for military use. After service with DLH, the Ha 139B was modified as the Ha 139B/Umbau (Reconstruction) with an extended glazed nose accommodating a navigator and a spherical Ikaria mount for a machine-gun. Further machine guns were mounted in the cockpit roof hatch and in lateral mountings on either side of the rear fuselage. The Ha 139B/Umbau was later modified into a mine sweeping (Minensuch) aircraft Ha 139B/MS fitted with a large magnetic sensing loop strung between the nose, floats, wing-tips, and tail unit.
Further development of the Ha 139 led to the land based version Blohm & Voss Bv 142 which had its first flight in October 1938 (Ref.: 24).